CONNECTING STRUCTURE FOR CHALCOGENIDE GLASS OPTICAL FIBER AND QUARTZ BASED OPTICAL FIBER AND OPTICAL DRIVING TYPE OPTICAL CONTROLLER USING THIS CONNECTING STRUCTURE

摘要

PROBLEM TO BE SOLVED: To make it possible to connect a chalcogenide glass optical fiber and quartz based glass optical fibers with low loss and low reflection by expanding the mode diameter of the first quartz fiber of the mode diameter approximately equal to the mode diameter of the small-diameter chalcogenide glass optical fiber to a tapered form so as to coincide with the mode diameter of the second fiber. SOLUTION: The chalcogenide glass optical fiber 43 and the quartz fiber 42 are formed nearly to the same core diameter and antireflection films 45, 46 are respectively formed on both. The two fibers 43, 42 are disposed to face each other to align their optical axes and are fixed to a guide 47 by using an adhesive 48. After the quartz fiber 42 and the quartz fiber 41 are fusion spliced, the quartz fiber 42 is heated to diffuse the germanium in the core, by which the core is worked to the taper shape 44 until its core diameter coincides nearly with the core diameter of the quartz fiber 41. As a result, the constitution of various kinds of the control optical switches of the low refractive index and low loss is made possible by using the chalcogenide glass optical fiber having high nonlinearity.